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71.
Cervical pedicle screws have been reported to be biomechanically superior to lateral mass screws. However, placement of these implants is a technical challenge. The purpose of this investigation was to use an anatomic and a clinical study to evaluate a technique for placement of the pedicle screws in the C7 vertebra using fluoroscopic imaging in only the anteroposterior (A/P) plane. Ten adult cadaver C7 vertebrae were used to record the pedicle width, inclination and a suitable entry point for placement of pedicle screws. A prospective study of 28 patients undergoing posterior instrumentation of the cervical spine with C7 pedicle screw placement was also performed. A total of 55 C7 pedicle screws were placed using imaging only in the A/P plane with screw trajectory values obtained by the anatomic study. Radiographs and CT scans were performed post-operatively. The average posterior pedicle diameter of C7 vertebra was 9.5 ± 1.2 mm in this study. The average middle pedicle diameter was 7.1 mm and the average anterior pedicle diameter was 9.2 mm. The average transverse pedicle angle was 26.8 on the right and 27.3 on the left. CT scans were obtained on 20 of 28 patients which showed two asymptomatic cortical wall perforations. One screw penetrated the lateral wall of the pedicle and another displayed an anterior vertebral penetration. There were no medial wall perforations. The preliminary results suggest that this technique is safe and suitable for pedicle screw placement in the C7 vertebra.  相似文献   
72.
Success of cricothyroidotomy depends on accurate identification of anatomical neck landmarks. Anaesthetists palpated the cricothyroid membrane of 28 obese and 28 non‐obese women in labour (cut‐off BMI 30 kg.m?2) and marked the entry point for device insertion with an ultraviolet invisible pen. Ultrasonography was used to mark the midpoint of the cricothyroid membrane and the distance between the two marks was measured. The median (IQR [range]) distance between the two marks was significantly greater in the obese than the non‐obese patients (5 (2–9.5 [0–34]) mm vs 1.8 (0.1–6 [0–15]) mm, respectively; p = 0.02). The cricothyroid membrane was accurately identified with digital palpation in only 39% (11/28) of obese compared with 71% (20/28) of non‐obese patients (p = 0.03). Increased neck circumference in obese patients was significantly associated with inaccuracy in locating the cricothyroid membrane. Percutaneous identification of the cricothyroid membrane in obese women in labour was poor. Pre‐procedural ultrasound may help improved the identification of neck landmarks for cricothyroidotomy.  相似文献   
73.
Study Type – Therapy (case series)
Level of Evidence 4

OBJECTIVES

To assess patients who had radical prostatectomy (RP) and pelvic lymph node dissection (PLND) for pT2–4 N0M0 prostate cancer, to determine if LN yield affects the risk of biochemical failure (BCF), as the extent of PLND at the time of RP has become increasingly uncertain with the decreasing trend in tumour stage.

PATIENTS AND METHODS

We reviewed the Columbia University Urologic Oncology Database for patients with pT2–4 N0M0 prostate cancer treated with RP from 1990 to 2005. Exclusion criteria included <12 months of follow‐up, incomplete clinical and pathological data, and neoadjuvant androgen‐deprivation therapy (ADT) or immediate adjuvant ADT or external beam radiotherapy. Unadjusted and adjusted models were used to determine the ability of clinical and pathological variables to predict BCF.

RESULTS

The final dataset included 964 patients, with a mean age of 60.5 years and median preoperative prostate‐specific antigen (PSA) level of 6.2 ng/mL. The median (range) LN yield was 7 (1–42) and the median follow‐up 59 (12–190) months. In the unadjusted and adjusted models, preoperative PSA, pathological Gleason score, pathological stage, surgical margin status and year of surgery were significant predictors of BCF. The LN group was not a significant predictor of BCF in both the unadjusted and adjusted model (P = 0.759 and 0.408, respectively). When patients were stratified into high‐ and low‐risk groups, LN yield remained an insignificant predictor of BCF.

CONCLUSION

A higher LN yield at the time of RP does not increase the chance of cure for patients with pT2–4N0M0 prostate cancer. This lack of a survival advantage holds true for patients with high‐risk disease.  相似文献   
74.
BACKGROUNDFollowing the successful Perioperative Surgical Home (PSH) practice for total knee arthroplasty (TKA) at our institution, the need for continuous improvement was realized, including the deimplementation of antiquated PSH elements and introduction of new practices. AIMTo investigate the transition from femoral nerve blocks (FNB) to adductor canal nerve blocks (ACB) during TKA. METHODSOur 13-month study from June 2016 to 2017 was divided into four periods: a three-month baseline (103 patients), a one-month pilot (47 patients), a three-month implementation and hardwiring period (100 patients), and a six-month evaluation period (185 patients). In total, 435 subjects were reviewed. Data within 30 postoperative days were extracted from electronic medical records, such as physical therapy results and administration of oral morphine equivalents (OME). RESULTSOur institution reduced FNB application (64% to 3%) and increased ACB utilization (36% to 97%) at 10 mo. Patients in the ACB group were found to have increased ambulation on the day of surgery (4.1 vs 2.0 m) and lower incidence of falls (0 vs 1%) and buckling (5% vs 27%) compared with FNB patients (P < 0.05). While ACB patients (13.9) reported lower OME than FNB patients (15.9), the difference (P = 0.087) did not fall below our designated statistical threshold of P value < 0.05.CONCLUSIONBy demonstrating closure of the “knowledge to action gap” within 6 mo, our institution’s findings demonstrate evidence in the value of implementation science. Physician education, technical support, and performance monitoring were deemed key facilitators of our program’s success. Expanded patient populations and additional orthopedic procedures are recommended for future study.  相似文献   
75.
Moderate-to-severe postoperative pain persists for longer than the duration of single-shot peripheral nerve blocks and hence continues to be a problem even with the routine use of regional anaesthesia techniques. The administration of local anaesthetic adjuncts, defined as the concomitant intravenous or perineural injection of one or more pharmacological agents, is an attractive and technically simple strategy to potentially extend the benefits of peripheral nerve blockade beyond the conventional maximum of 8–14 hours. Historical local anaesthetic adjuncts include perineural adrenaline that has been demonstrated to increase the mean duration of analgesia by as little as just over 1 hour. Of the novel local anaesthetic adjuncts, dexmedetomidine and dexamethasone have best demonstrated the capacity to considerably improve the duration of blocks. Perineural dexmedetomidine and dexamethasone increase the mean duration of analgesia by up to 6 hour and 8 hour, respectively, when combined with long-acting local anaesthetics. The evidence for the safety of these local anaesthetic adjuncts continues to accumulate, although the findings of a neurotoxic effect with perineural dexmedetomidine during in-vitro studies are conflicting. Neither perineural dexmedetomidine nor dexamethasone fulfils all the criteria of the ideal local anaesthetic adjunct. Dexmedetomidine is limited by side-effects such as bradycardia, hypotension and sedation, and dexamethasone slightly increases glycaemia. In view of the concerns related to localised nerve and muscle injury and the lack of consistent evidence for the superiority of the perineural vs. systemic route of administration, we recommend the off-label use of systemic dexamethasone as a local anaesthetic adjunct in a dose of 0.1–0.2 mg.kg−1 for all patients undergoing surgery associated with significant postoperative pain.  相似文献   
76.
Association of hyperglycemia with increased mortality after severe burn injury   总被引:13,自引:0,他引:13  
OBJECTIVE: To assess results of exchange nailing in nonunion after intramedullary (IM) nailing of humeral shaft fractures. METHODS: This was a retrospective study; 24 patients with nonunion after IM nailing of humeral shaft fractures were reviewed. In 13 cases, nonunion was treated using exchange nailing, and 11 patients were treated nonoperatively. Union was assessed from radiographs. Shoulder joint symptoms and function were assessed after a mean 4.7 years' follow-up using Constant-Murley scoring and self-administered questionnaires devised by L'Insalata et al. RESULTS: Single or repeated exchange nailing resulted in union in 6 of 13 patients. Shoulder joint function was satisfactory (mean Constant-Murley score of 72) for those patients whose fracture eventually united and poor (mean Constant-Murley score of 39) for those left with nonunion. CONCLUSION: Exchange nailing results in a poor union rate in nonunion after IM nailing of humeral shaft fractures. Permanent nonunion of the humeral shaft leaves the patient with severe disability.  相似文献   
77.
78.
Context Sunitinib malate is an oral tyrosine kinase inhibitor used in the treatment of renal cell carcinoma (RCC) and gastrointestinal stromal tumours. Hypothyroidism has been observed in patients treated with sunitinib, but the mechanism whereby sunitinib induces hypothyroidism is unknown. Objective To describe a series of six patients who developed thyrotoxicosis while on sunitinib for metastatic RCC. Setting The study was conducted at Austin Health, a tertiary teaching hospital in Melbourne, Australia. Results Two patients developed severe thyrotoxicosis within 10 weeks after commencing sunitinib. In contrast, in the four patients who presented with later onset (16–30 weeks) thyrotoxicosis, the thyrotoxicosis was relatively mild, self‐limiting and rapidly progressed to hypothyroidism. These patients experienced recurrent episodes of thyrotoxicosis in temporal relation to their cyclical sunitinib treatment. One patient had cytological evidence of lymphocytic thyroiditis. Conclusions These findings suggest that sunitinib‐induced hypothyroidism may be a consequence of preceding thyroiditis with associated transient thyrotoxicosis. As predictive factors are currently unknown, we suggest regular monitoring of thyroid function in all patients commenced on sunitinib. Clinicians treating patients with sunitinib or other similar kinase inhibitors should to be alerted to thyroid dysfunction as a potential toxicity of these agents.  相似文献   
79.
80.

Purpose of Review

This review aims to describe the nonreconstructive options for treating ulnar collateral ligament (UCL) injuries ranging from nonoperative measures, including physical therapy and biologic injections, to ligament repair with and without augmentation.

Recent Findings

Nonoperative options for UCL injuries include guided physical therapy and biologic augmentation with platelet-rich plasma (PRP). In some patients, repair of the UCL has shown promising return to sport rates by using modern suture and suture anchor techniques. Proximal avulsion injuries have shown the best results after repair. Currently, there is growing interest in augmentation of UCL repair with an internal brace.

Summary

The treatment of UCL injuries involves complex decision making. UCL reconstruction remains the gold standard for attritional injuries and complete tears, which occur commonly in professional athletes. However, nonreconstructive options have shown promising results for simple avulsion or partial thickness UCL injuries. Future research comparing reconstructive versus nonreconstructive options is necessary.
  相似文献   
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